Floating and bedfast lake ice regimes across Arctic Alaska using space-borne SAR imagery from 1992-2016

This dataset contains seven shapefiles of lake-rich regions in Arctic Alaska which detail late-winter lake ice regimes. Late-winter lake ice regimes are controlled by water depth relative to maximum ice thickness (MIT). When MIT exceeds maximum water depth, lakes freeze to the bottom with bedfast ic...

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Bibliographic Details
Main Author: Engram, Melanie
Format: Dataset
Language:English
Published: Arctic Data Center 2018
Subjects:
SAR
Ice
Online Access:https://dx.doi.org/10.18739/a2cj87k8h
https://arcticdata.io/catalog/#view/doi:10.18739/A2CJ87K8H
id ftdatacite:10.18739/a2cj87k8h
record_format openpolar
spelling ftdatacite:10.18739/a2cj87k8h 2023-05-15T14:54:31+02:00 Floating and bedfast lake ice regimes across Arctic Alaska using space-borne SAR imagery from 1992-2016 Engram, Melanie 2018 text/xml https://dx.doi.org/10.18739/a2cj87k8h https://arcticdata.io/catalog/#view/doi:10.18739/A2CJ87K8H en eng Arctic Data Center Lake ice regime Earth Science Climate indicator Permafrost Thaw Talik Lake Ice Synthetic Aperture Radar SAR dataset Dataset 2018 ftdatacite https://doi.org/10.18739/a2cj87k8h 2021-11-05T12:55:41Z This dataset contains seven shapefiles of lake-rich regions in Arctic Alaska which detail late-winter lake ice regimes. Late-winter lake ice regimes are controlled by water depth relative to maximum ice thickness (MIT). When MIT exceeds maximum water depth, lakes freeze to the bottom with bedfast ice (BI) and when MIT is less than maximum water depth lakes have floating ice (FI). In this study, we use a combination of ERS-1/2, RADARSAT-2, Envisat, and Sentinel-1 synthetic aperture radar (SAR) imagery for the seven lake-rich regions to analyze lake ice regime extents and dynamics over a 25-year period (1992-2016). This research was a part of the Arctic Lake Ice Systems Science (ALISS) project (http://arcticlakeice.org/) . Our interactive threshold classification method determines a unique statistic-based intensity threshold for each SAR scene, allowing for the comparison of classification results from C-band SAR data acquired with different polarizations and incidence angles. Additionally, our novel method accommodates declining signal strength in aging extended-mission satellite SAR instruments. Comparison of SAR ice regime classifications with extensive field measurements from six years yielded a 93% accuracy. Significant declines in BI regimes were only observed in the Fish Creek area with 3% of lakes exhibiting transitional ice regimes - lakes that switch from BI to FI during this 25-year period. This analysis suggests that the potential conversion from BI to FI regimes is primarily a function of lake depth distributions in addition to regional differences in climate variability. Remote sensing of lake ice regimes with C-band SAR is a useful tool to monitor the associated thermal impacts on permafrost, since lake ice regimes can be used as a proxy for of sub-lake permafrost thaw, considered by the Global Climate Observing System as an Essential Climate Variable (ECV). Continued winter warming and variable snow conditions in the Arctic are expected and our long-term analysis provides a valuable baseline for predicting where potential future lake ice regimes shifts will be most pronounced. Dataset Arctic Ice permafrost Alaska DataCite Metadata Store (German National Library of Science and Technology) Arctic Arctic Lake ENVELOPE(-130.826,-130.826,57.231,57.231) Talik ENVELOPE(146.601,146.601,59.667,59.667) Winter Lake ENVELOPE(-112.918,-112.918,64.484,64.484)
institution Open Polar
collection DataCite Metadata Store (German National Library of Science and Technology)
op_collection_id ftdatacite
language English
topic Lake ice regime
Earth Science
Climate indicator
Permafrost Thaw
Talik
Lake Ice
Synthetic Aperture Radar
SAR
spellingShingle Lake ice regime
Earth Science
Climate indicator
Permafrost Thaw
Talik
Lake Ice
Synthetic Aperture Radar
SAR
Engram, Melanie
Floating and bedfast lake ice regimes across Arctic Alaska using space-borne SAR imagery from 1992-2016
topic_facet Lake ice regime
Earth Science
Climate indicator
Permafrost Thaw
Talik
Lake Ice
Synthetic Aperture Radar
SAR
description This dataset contains seven shapefiles of lake-rich regions in Arctic Alaska which detail late-winter lake ice regimes. Late-winter lake ice regimes are controlled by water depth relative to maximum ice thickness (MIT). When MIT exceeds maximum water depth, lakes freeze to the bottom with bedfast ice (BI) and when MIT is less than maximum water depth lakes have floating ice (FI). In this study, we use a combination of ERS-1/2, RADARSAT-2, Envisat, and Sentinel-1 synthetic aperture radar (SAR) imagery for the seven lake-rich regions to analyze lake ice regime extents and dynamics over a 25-year period (1992-2016). This research was a part of the Arctic Lake Ice Systems Science (ALISS) project (http://arcticlakeice.org/) . Our interactive threshold classification method determines a unique statistic-based intensity threshold for each SAR scene, allowing for the comparison of classification results from C-band SAR data acquired with different polarizations and incidence angles. Additionally, our novel method accommodates declining signal strength in aging extended-mission satellite SAR instruments. Comparison of SAR ice regime classifications with extensive field measurements from six years yielded a 93% accuracy. Significant declines in BI regimes were only observed in the Fish Creek area with 3% of lakes exhibiting transitional ice regimes - lakes that switch from BI to FI during this 25-year period. This analysis suggests that the potential conversion from BI to FI regimes is primarily a function of lake depth distributions in addition to regional differences in climate variability. Remote sensing of lake ice regimes with C-band SAR is a useful tool to monitor the associated thermal impacts on permafrost, since lake ice regimes can be used as a proxy for of sub-lake permafrost thaw, considered by the Global Climate Observing System as an Essential Climate Variable (ECV). Continued winter warming and variable snow conditions in the Arctic are expected and our long-term analysis provides a valuable baseline for predicting where potential future lake ice regimes shifts will be most pronounced.
format Dataset
author Engram, Melanie
author_facet Engram, Melanie
author_sort Engram, Melanie
title Floating and bedfast lake ice regimes across Arctic Alaska using space-borne SAR imagery from 1992-2016
title_short Floating and bedfast lake ice regimes across Arctic Alaska using space-borne SAR imagery from 1992-2016
title_full Floating and bedfast lake ice regimes across Arctic Alaska using space-borne SAR imagery from 1992-2016
title_fullStr Floating and bedfast lake ice regimes across Arctic Alaska using space-borne SAR imagery from 1992-2016
title_full_unstemmed Floating and bedfast lake ice regimes across Arctic Alaska using space-borne SAR imagery from 1992-2016
title_sort floating and bedfast lake ice regimes across arctic alaska using space-borne sar imagery from 1992-2016
publisher Arctic Data Center
publishDate 2018
url https://dx.doi.org/10.18739/a2cj87k8h
https://arcticdata.io/catalog/#view/doi:10.18739/A2CJ87K8H
long_lat ENVELOPE(-130.826,-130.826,57.231,57.231)
ENVELOPE(146.601,146.601,59.667,59.667)
ENVELOPE(-112.918,-112.918,64.484,64.484)
geographic Arctic
Arctic Lake
Talik
Winter Lake
geographic_facet Arctic
Arctic Lake
Talik
Winter Lake
genre Arctic
Ice
permafrost
Alaska
genre_facet Arctic
Ice
permafrost
Alaska
op_doi https://doi.org/10.18739/a2cj87k8h
_version_ 1766326231936008192